1. Field of The Invention
The present invention is directed to the field of musical instruments. More particularly, it relates to an apparatus for instantaneously varying the tension on a drum head to change the pitch of the instrument while it is being played.
2. Description of Related Art
The pitch of a percussion type musical instrument, such as a drum, is dependent upon the tension in the head covering the instrument. The pitch of the tone produced by striking the instrument is raised by increasing the tension in the head. Similarly, by decreasing the tension in the head, the pitch of the tone is lowered.
A drum head may be manually tensioned before a performance to produce a desired tone. An apparatus for manually tensioning a drum head is disclosed in U.S. Pat. No. 2,061,244. This apparatus requires that the musician manually turn a crank to change the pitch of the drum. When manual tensioning is employed it is very difficult or impossible to vary the tone of the instrument during a performance and several drums, each tuned to a different pitch, may be required to perform a given composition. An electronic device for automatically tuning a drum to a selected pitch is disclosed in U.S. Pat. No. 4,023,462. This device eliminates the need for the musician to manually adjust the tension in the drum head, but it is not entirely suitable for varying the pitch of the drum repeatedly during a performance.
It is therefore desirable for a musician to have the capability of instantaneously changing the pitch of a drum during a performance. In addition to providing a range of tones from a single instrument, such a capability may reduce the number of drums required for the performance.
At least one technique by which drum head tension may be varied during a performance is known in the prior art. This technique, disclosed in U.S. Pat. No. 3,590,680, involves pressurizing the drum with compressed air or gas and selectively varying the gas pressure, thereby varying the pitch of the drum. This method of drum pitch control requires that the drum itself be made essentially gas tight. Many types of drums, however, are made of gas-permeable materials and/or are designed with open-ended barrels to achieve specific sound qualities. The gas pressure method of pitch control is thus inapplicable to most drums.
Because it is often desirable to vary the pitch of drums during a musical performance, there is a need for a drum head tension control system which is adaptable to all drum types.